A numerical approach to predict the SOFC fracture : the case of an anode supported cell.

International audienceThe purpose of this work is focused on the calculation of the stress field inside planar anode supported cells. The cell fracture was estimated through the statistical approach of Weibull. After elaboration, a high residual compressive stress was calculated in the thin electrolyte layer. A slight tensile stress was pointed out in the anode in a region close the anode/electrolyte interface. For high electrolyte thickness (>20 mu m), this tension leads to low survival probabilities of the anode. At SOFC operating temperature, the elaboration stress is partially relaxed. In this condition, the thermal cycling between the room temperature to the SOFC operating one should not induced any cell degradation. The first cermet reoxidation step was also analyzed. This study has shown that the cathode is damaged as soon as the anodic expansion reaches values between 0.05-0.09%. The electrolyte fracture is predicted to occur for anodic expansion ranging between 0.12-0.15%